Recently, it has been required to reclaim and reuse waste plastics having a paint film in view of environmental pollution. The paint films made on these waste plastics are not melted by heat or not dissolved by a solvent, because the paint films are bridged and thermoset generally in a three dimensional network structure. To remove the paint films, there is no other process than mechanically cutting away the paint films. Namely, a process is assumed in which the paint films are mechanically removed by sandblasting beforehand and then the waste plastics are pulverized to produce reclaimed resin compositions for molding. This process, however, is not appropriate for industrial use, because it takes a lot of time to remove the paint films in the case of parts having complicated solid surfaces and the paint films cannot be completely removed.
Therefore, as one of the other processes for reclaiming waste plastics having a thermosetting paint film, a process has been conventionally used in which the above waste plastics which has been pulverized is kneaded as it is by a kneading machine such as a multiple spindle extruder in order to produce a reclaimed resin composition for molding. In this process, however, the paint film components are not melted in the kneading machine, and exist as foreign matters in the reclaimed resin composition for molding. Therefore, moldings of the reclaimed resin composition are decreased in mechanical properties. The decrease in the mechanical properties is remarkably shown in impact strength particularly. As a result, there arises a problem that the use of the reclaimed resin composition for molding has to be limited to ones which do not require impact strength.
The present invention has been conceived in view of the above circumstances. It is an object of the present invention to reclaim waste plastics having a paint film without removing the paint film and to produce a reclaimed resin composition for molding which does not have a large decrease in impact strength and which can produce plastic products having approximately equal properties to those of new plastics.